Mao Zedong, Pol Pot, and Kim Il Sung's brutality impacted not only their own nations, but also each others, and in fact, many of Asia's nations. All of these dictators studied in the USSR under Joseph Stalin and based their rules on Marxism. Both Pol Pot and Kim Il Sung also learned from Mao Zedong.
The people in these nations suffered many deaths under their rulers. Mao is estimated to have killed 14-20 million Chinese during his rein, Pol Pot is estimated to have killed one to three million during his four years in power, and Kim Il Sung is estimated to have killed over three million. All citizens lived in great fear of their government. Death was common in all of their countries for any who spoke out against these men.
The other countries of Asia were greatly impacted during this time as well. Both the Vietnam and Korean Wars had all of these men fighting the United States and its allies. They also relied heavily on the Soviet Union for aid and arms and both China and North Korea engaged in fighting for freedom from Japan.
Unfortunately, much of the damage caused by these men is still causing problems today. In China, Mao Zedong brought about the communism that is still the rule of the country today. Its leader Hu Jintao moved up the communist ranks and took control in 2000. The government of China is still brutal housing over 300,000 people in 're-education' sentences and executing over 4000 people each year, more than any other nation.
Cambodia is also still dealing with leftover problems from Pol Pot. People were still fighting the new government in his name until his death in 1998. The United Nations is working on military tribunals to try key members of his regime for genocide. They are also still uncovering mass graves, although over 19,000 have been found as of 2001.
North Korea is probably the worst off of all of these nations though. Kim Il Sung died in 1994 leaving his son Kim Jung Il in charge. But, in 1998, Korea's constitution was amended and declared Kim Il Sung president for eternity. Since then Kim Jung Il took control, millions more North Koreans have died from starvation. The United Nations and the United States have been negotiating with Kim Jung Il about possible nuclear weapons, and it was declared one of the Axes of Evil by President Bush in 2002. Their foreign debt is estimated in the billions.